Fix metadata location when file system doesn't span the partition
Pad the sparse image with a zero fill chunk to correctly position
verity and FEC metadata at the end of the partition.
Bug: 27073791
Change-Id: I9f70d579a42e5007d50e9c02a98a608d2815f0ed
(cherry picked from commit 6a8781a25113b9b49dddc8c8e043c27d5a943e3a)
diff --git a/tools/releasetools/sparse_img.py b/tools/releasetools/sparse_img.py
index 013044f..4ba7560 100644
--- a/tools/releasetools/sparse_img.py
+++ b/tools/releasetools/sparse_img.py
@@ -31,8 +31,9 @@
the form of a string like "0" or "0 1-5 8".
"""
- def __init__(self, simg_fn, file_map_fn=None, clobbered_blocks=None):
- self.simg_f = f = open(simg_fn, "rb")
+ def __init__(self, simg_fn, file_map_fn=None, clobbered_blocks=None,
+ mode="rb", build_map=True):
+ self.simg_f = f = open(simg_fn, mode)
header_bin = f.read(28)
header = struct.unpack("<I4H4I", header_bin)
@@ -44,7 +45,7 @@
chunk_hdr_sz = header[4]
self.blocksize = blk_sz = header[5]
self.total_blocks = total_blks = header[6]
- total_chunks = header[7]
+ self.total_chunks = total_chunks = header[7]
if magic != 0xED26FF3A:
raise ValueError("Magic should be 0xED26FF3A but is 0x%08X" % (magic,))
@@ -61,6 +62,9 @@
print("Total of %u %u-byte output blocks in %u input chunks."
% (total_blks, blk_sz, total_chunks))
+ if not build_map:
+ return
+
pos = 0 # in blocks
care_data = []
self.offset_map = offset_map = []
@@ -126,6 +130,20 @@
else:
self.file_map = {"__DATA": self.care_map}
+ def AppendFillChunk(self, data, blocks):
+ f = self.simg_f
+
+ # Append a fill chunk
+ f.seek(0, os.SEEK_END)
+ f.write(struct.pack("<2H3I", 0xCAC2, 0, blocks, 16, data))
+
+ # Update the sparse header
+ self.total_blocks += blocks
+ self.total_chunks += 1
+
+ f.seek(16, os.SEEK_SET)
+ f.write(struct.pack("<2I", self.total_blocks, self.total_chunks))
+
def ReadRangeSet(self, ranges):
return [d for d in self._GetRangeData(ranges)]